In the present study, the structural properties, as well as the photodegradation performance of methylene blue (MB) and rhodamine B (Rh B) using hydrothermal synthesized AgxSn1–xO2 (0 ≤ x ≤ 1) nanocomposites were studied. The study was investigated using various techniques including EDS, XRD, FE-SEM, HR-TEM, photoluminescence spectroscopy, N2 adsorption-desorption, GC-MS, and a double-beam spectrophotometer. The tetragonal SnO2 phase dominates, while the cubic Ag2O phase appears at larger x ratios (x ≥ 0.5). The crystallite and particle sizes were slightly raised for a low Ag ratio but dramatically increased for higher x ratios. Different morphologies emerge depending on the composition, such as spherical and irregular particles for x = 0 and 1, sheet-like morphology for x = 0.05, 0.2, and 0.4, and worm-like morphology for x = 0.5. The maximum surface area was calculated using the BET method to be 358 and 354 m2/g for x = 0.2 and 0.4, respectively. The direct optical band gap depends on the x ratio and the crystallite size and equals 3.95eV and 3.70eV for x = 0 and x = 1, respectively. The synthesized AgxSn1–xO2 composites demonstrated excellent photodegradation efficiency (η) towards MB and Rh B. The majority of compositions had high η towards MB and the highest value of 99.6% was attained using Ag0.4Sn0.6O2 under the UV-visible irradiation for 1.5h. Also, synthetic composites demonstrated efficient photodegradation of Rh B, particularly for higher Ag content (η = 94.4% at x = 0.5). The catalysts revealed acceptable reusability and stability, and the degraded products were studied using the GC-MS technique with a proposed mechanism of degradation. The improvement in photodegradation of MB and Rh B dyes can be attributed to an increase in surface area, as well as the development of shape and optical characteristics.
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